MHT CET · Physics · Mathematics in Physics
The angle subtended by the vector \(\vec{A}=4 \hat{\imath}+3 \hat{\jmath}+12 \hat{k}\) with the \(\mathrm{x}\) -axis is
- A \(\sin ^{-1}\left(\frac{4}{13}\right)\)
- B \(\cos ^{-1}\left(\frac{3}{13}\right)\)
- C \(\cos ^{-1}\left(\frac{4}{13}\right)\)
- D \(\sin ^{-1}\left(\frac{3}{13}\right)\)
Answer & Solution
Correct Answer
(C) \(\cos ^{-1}\left(\frac{4}{13}\right)\)
Step-by-step Solution
Detailed explanation
\(\vec{A}=4 i+3 j+12 k\)
\(p=i\)
\(\cos \theta \frac{\mid \vec{A} \cdot \vec{B}}{|A||B|} \Rightarrow \frac{4}{\sqrt{16+9+144} \times 1}\)
\(\theta \begin{aligned} \Rightarrow \cos ^{\prime} 1 / 13 & \end{aligned}\)
\(p=i\)
\(\cos \theta \frac{\mid \vec{A} \cdot \vec{B}}{|A||B|} \Rightarrow \frac{4}{\sqrt{16+9+144} \times 1}\)
\(\theta \begin{aligned} \Rightarrow \cos ^{\prime} 1 / 13 & \end{aligned}\)
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